Internal combustion engine are continually being refined to increase the output of the engine as well as reduce the engine's weight and/or size. Boosting devices, such as turbochargers and superchargers, have been added to engines so that the engines may have output similar to larger displacement engines without the fuel economy and emissions of larger displacement engines. Further, vehicle fuel economy may be improved in vehicles having smaller engines at least in part because smaller engines may weigh less than larger displacement engines. Alternatively, output power of an engine may be substantially increased without adding a significant amount of weight to the engine. Additional techniques for increasing engine power such as direct injection may also be used without significantly increasing the engine's weight.
However, decreasing engine size and/or increasing engine power output can increase stress on the engine components. Such concerns may be particularly present for boosted engines which typically have a high power to weight ratio as compared to naturally aspirated engines. Therefore, some boosted engines are comprised of increased amounts of material, such as aluminum, to reinforce the cylinder block. But, increasing the amount of material used to form the cylinder block can increase engine weight as well as size, thereby undermining the basic objective of increasing the engine's power to weight ratio.
The inventors herein have recognized the challenges of boosting a weight reduced engine and have provided a structural frame. The structural frame may include a bottom oil pan engaging surface and first and second cylinder block engaging surfaces, the first and second surfaces positioned above the bottom oil pan engaging surface at a height that is above a centerline of a crankshaft when the structural frame is coupled to a cylinder block. The structural frame may further include a structural frame lubrication passage traversing at least a portion of the structural frame.
In this way, lubrication passages may be internally routed through the structural frame. The internal routing of the lubrication passages through the structural frame increases the compactness of the engine. Furthermore, external lubricant routing lines may not be needed when the lubrication lines are internally routed through the cylinder block assembly. Therefore, the likelihood of rupturing a lubrication line during engine installation may be reduced and in some cases substantially eliminated when lubrication passages are internally routed through the structural frame. Furthermore, the cost of manufacturing of the cylinder block assembly may be reduced when lubrication passages are internally routed through the structural frame.
This Summary is provided to introduce a selection of concepts in a simplified form that are further described below in the Detailed Description. This Summary is not intended to identify key features or essential features of the claimed subject matter, nor is it intended to be used to limit the scope of the claimed subject matter. Furthermore, the claimed subject matter is not limited to implementations that solve any or all disadvantages noted in any part of this disclosure.